BACKGROUND The active metabolite (1, 25-dihydroxycholecalciferol) of vitamin D (25-hydroxycholecalciferol) leads to activation of macrophages and deficiency of vitamin D seems to be involved in the risk of tuberculosis. The effects of vitamin D are exerted by interaction with the vitamin D receptor (VDR) and may be influenced by polymorphism in the VDR gene. In this study, variation in the VDR ...

BACKGROUND Numerous observational studies have found supplemental calcium and vitamin D to be associated with reduced risk of common cancers. However, interventional studies to test this effect are lacking. OBJECTIVE The purpose of this analysis was to determine the efficacy of calcium alone and calcium plus vitamin D in reducing incident cancer risk of all types. DESIGN This was a 4-y, pop...

A pharmacokinetic study was conducted to assess the biochemical dose-response and tolerability of high-dose prenatal vitamin D3 supplementation in Dhaka, Bangladesh (23°N). Pregnant women at 27-30 weeks gestation (n = 28) were randomized to 70,000 IU once + 35,000 IU/week vitamin D3 (group PH: pregnant, higher dose) or 14,000 IU/week vitamin D3 (PL: pregnant, lower dose) until delivery. A group...

OBJECTIVE A protective association between higher vitamin D levels and the onset of multiple sclerosis (MS) has been demonstrated; however, its role in modulating MS clinical course has been little studied. We investigated whether higher levels of serum 25-hydroxyvitamin D (25-OH-D) were associated with a lower risk of relapses in people with MS. METHODS We conducted a prospective cohort stud...

BACKGROUND Adults living in the sunny Australian climate are at high risk of skin cancer, but vitamin D deficiency (defined here as a serum 25-hydroxyvitamin D (25(OH)D) concentration of less than 50 nmol/L) is also common. Vitamin D deficiency may be a risk factor for a range of diseases. However, the optimal strategies to achieve and maintain vitamin D adequacy (sun exposure, vitamin D supple...

In 3 trials, the effects of dietary supplementation with phytase (PHY) and 25-hydroxycholecalciferol (25-D3) on the digestive and reproductive organ characteristics of commercial layers that were inoculated prelay (12 wk of age) or at the onset of lay (22 wk of age) with F-strain Mycoplasma gallisepticum (FMG) were assessed at 58 wk of age. Experimental layer diets that included a basal control...

The German Nutrition Society raised in 2012 the recommended daily vitamin D intake from 200 to 800 international units (IU) to achieve 25-hydroxyvitamin D (25(OH)D) levels of at least 50 nmol/L, even when endogenous vitamin D synthesis is minimal such as in winter. We aimed to evaluate this recommendation in women of childbearing age. This is a single-center, randomized, open trial conducted fr...

BACKGROUND The aims of this study were to determine if pregnant women consumed the recommended vitamin D through diet alone or through diet and supplements, and if they achieved the current reference range vitamin D status when their reported dietary intake met the current recommendations. METHODS Data and banked blood samples collected in second trimester from a subset of 537 women in the AP...

BACKGROUND Vitamin D is an important factor in human health. Yet, vitamin D deficiency is very common. We aimed to confirm serum 25-hydroxyvitamin D (25OHD) concentration change after sunlight exposure and to elucidate the relationship between the amount of sunlight exposure and serum 25OHD level change by ambulatory lux meter and sunlight exposure questionnaire. METHODS Twenty healthy young ...

Vitamin D is a pro-hormone that plays an important role in body calcium regulation. Vitamin D toxicity occurs rarely due to its wide therapeutic index. A 38-year-old Iranian man was admitted to our hospital with a diagnosis of vitamin D toxicity. Laboratory test revealed hypercalcemia and elevated 25-hydroxyvitamin D (25(OH)D) level. Despite the cessation of vitamin D intake and diuretic treatm...